The aim of this systematic review and network meta-analysis was to comprehensively evaluate and compare the effectiveness of diverse therapies for disc displacement (DD) of the temporomandibular joint (TMJ). An electronic search of PubMed, Embase, the Cochrane Library, the China Academic Journals full-text database (CNKI), and Wanfang databases was performed to identify relevant studies available up to 31 July 2021. Study selection, data extraction, and quality assessment were performed for all included studies, while the outcomes of interest contained post-therapeutic maximum mouth opening and pain intensity. Interventions consisted of arthrocentesis, injections with diverse drugs, occlusal splints, or a combination of two to three of the above. Controls were regarded as oral analgesics, self-exercise, massage, or health instruction. Twenty-six studies appeared to meet the inclusion criteria and were subjected to further examination. Our data of the entire network showed that the most invasive therapies performed better than non-invasive therapies, while arthrocentesis + platelet-rich plasma injection and platelet-rich plasma injection in Grade I performed well in both mouth opening improvement and pain alleviation. Platelet-rich plasma injection is probably the best treatment overall for patients with DD owing to its anti-inflammatory, analgesic, and lubricating effects.